Process for producing aromatic sulfides

ABSTRACT

A process which can be used to produce an aromatic sulfide compound having the formula of (R 4-n )(X n )(W)Ar--S--R&#39; is provided. The process comprises contacting, in the presence of a surfactant, a halo-substituted aromatic compound in an aqueous solution with a salt of a mercaptan under conditions sufficient to produce the aromatic sulfide in which the halo-substituted aromatic compound and salt of mercaptan are each present in an amount effective to synthesize the aromatic sulfide wherein R is hydrogen or a hydrocarbyl radical, X is a hlogen, n is a number from 0 to 3, W is a substituent, Ar is an aromatic ring, and R&#39; is a hydrocarbyl radical.

FIELD OF THE INVENTION

The present invention relates to a process for producing an aromaticsulfide from a halo-substituted aromatic compound and a salt of amercaptan.

BACKGROUND OF THE INVENTION

Aromatic sulfides such as nitrophenyl sulfides are generally a class ofchemicals used as intermediates for the synthesis of other chemicals.For example, 2-chloro-6-nitrophenyl isopropyl sulfide or2-chloro-6-nitrophenylthioisopropyl ether can be used to synthesizeagricultural chemicals and 3-chloro-6-nitrophenyl benzyl sulfide(2-benzylthio-4-chloronitrobenzene) can be used to synthesize diazoxidewhich is used as antihypertensive agent for reducing high bloodpressure.

Generally, nitrophenyl sulfides can be made from halo-substitutedaromatic compounds in displacement reactions. In the displacementreactions, nucleophiles having a sulfur atom are capable of displacingan electronegative halogen group from the aromatic compounds therebyforming a bond with electron-deficient carbon of the aromatic compounds.For example, it has been reported that 6-nitrophenyl benzyl sulfide issynthesized by reacting 2,4-dichloro nitrobenzene with benzyl mercaptanin the presence of potassium hydroxide in ethanol solution. Suchsynthetic route requires the use of an organic solvent.

Attempts to synthesize an aromatic sulfide such as a nitrophenyl sulfidewithout using an organic solvent were unsuccessful because the reactionrate was slow, the conversion of reactants was low, many by-productswere formed, the yield was low, and the purity of the product was alsolow. Therefore there is a need to develop an improved process forproducing an aromatic sulfide using an aqueous medium. Development ofsuch a process would also significantly contribute to the art ofaromatic sulfide synthesis.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a process for producingan aromatic sulfide without using an organic solvent. Another object ofthe present invention is to provide a process for producing an aromaticsulfide in high yield and purity. A further object of the presentinvention is to provide a process for producing an aromatic sulfidewhich does not require further purification. An advantage of the presentinvention is that a high conversion of reactants to an aromatic sulfide.Another advantage of the present invention is that the invention processprovides a fast reaction rate.

According to the present invention, a process that can be used forproducing an aromatic sulfide is provided. The process comprisescontacting, in the presence of a surfactant, a halo-substituted aromaticcompound with a salt of a mercaptan in an aqueous medium under acondition sufficient to effect the synthesis of an aromatic sulfidewhere the halo-substituted aromatic compound and the salt of a mercaptanare each present in an effective amount for the synthesis of an aromaticsulfide. A salt of a mercaptan can also be made in-situ by contacting anammonium hydroxide or a metal hydroxide with a mercaptan.

DETAILED DESCRIPTION OF THE INVENTION

According to the present invention, the term aromatic sulfide is definedas an organic sulfide compound having the formula of(R_(4-n))(X_(n))(W)Ar--S--R' wherein each R can be the same or differentand is each independently selected from the group consisting ofhydrogen, hydrocarbyl radicals, and combinations of any two or morethereof in which the hydrocarbyl radical is selected from the groupconsisting of alkyl radicals, akenyl radicals, alkaryl radicals, aralkylradicals, cycloalkyl radicals, cycloalkenyl radicals, and combinationsof any two or more thereof; each X is a halogen; n is a number from 0 to3; W is a substitutent selected from the group consisting of --NO₂,--SO₃ H, --CHO, --COOH, --NO, --N⁺ ₂, --CN, --COR, --COO⁻, SO₃ ⁻, --SO₂CH₃, --CF₃, --N⁺ (CH₃)₃, and combinations of any two or more thereof; Aris a phenyl group, naphthyl group, biphenyl group or combinations of anytwo or more thereof; R' is selected from the group consisting of alkylradicals, akenyl radicals, alkaryl radicals, aralkyl radicals,cycloalkyl radicals, cycloalkenyl radicals, R--W, and combinations ofany two or more thereof wherein R and W are the same as those disclosedabove; and each hydrocarbyl radical has 1 to about 30, preferably 1 toabout 20, and most preferably 1 to 15 carbon atoms.

Examples of suitable aromatic sulfides include, but are not limited to,2-chloro-6-nitrophenyl isopropyl sulfide. 3-chloro-6-nitrophenyl benzylsulfide, 3-chloro-6-nitrophenyl isopropyl sulfide,4-chloro-6-nitrophenyl isopropyl sulfide, 2-chloro-6-nitrophenyl methylsulfide, 3-chloro-6-nitrophenyl methyl sulfide, 4-chloro-6-nitrophenylmethyl sulfide, 2-chloro-6-nitrophenyl benzyl sulfide,4-chloro-6-nitrophenyl benzyl sulfide, 3-chloro-6-nitrophenyl cyclohexylsulfide. 4-nitrophenyl methyl sulfide, 4-nitrophenyl isopropyl sulfide.4-nitrophenyl benzyl sulfide, 3-nitrophenyl methyl sulfide,3-nitrophenyl isopropyl sulfide, 3-nitrophenyl benzyl sulfide,4-benzylthiobenzaldehyde, 4-isopropylthiobenzaldehyde,3-benzylthiobenzoic acid, 4-methylthiomethylbenzoate, and combinationsof any two or more thereof.

The halo-substituted aromatic compound suitable for use in the presentinvention has a general formula of (R_(4-n))(X_(n+1))WAr wherein R, n,X, W, and Ar are the same as those disclosed above; and it is preferredthat one, and only one, X be at the ortho-position to W in the Ar ring.

Examples of suitable halo-substituted aromatic compounds include, butare not limited to, 2,3-dichloronitrobenzene, 3,4-dichloronitrobenzene,2,4-dichloronitrobenzene, 2,3-difluoronitrobenzene,3,4-difluoronitrobenzene, 2,4-difluoronitrobenzene,2,3-dibromonitrobenzene, 3,4-dibromonitrobenzene,2,4-dibromonitrobenzene, 2,4-dichloro-5-nitrotoluene,3,4-dichloro-5-nitrobenzene, 4-chlorobenzaldehyde, 4-bromobenzaldehyde,4-iodobenzaldehyde, 3-chlorobenzaldehyde, 3-bromobenzaldehyde,4-chlorobenzoic acid, 4-bromobenzoic acid, 3-iodobenzoic acid,4-chloromethylbenzoate, 4-bromomethylbenzoate, and combinations of anytwo or more thereof.

These halo-substituted aromatic compounds generally are commerciallyavailable or can be made by any methods known to one skilled in the art.Because the methods are well known, description of which is omittedherein for the interest of brevity.

A salt of a mercaptan suitable for use in the present invention can beany salt of any mercaptan so long as the salt can provide a nucleophilefor displacing the activated halogen on the halo-substituted aromaticcompound. Generally, a salt of a mercaptan has the formula of MSR'wherein M can be an alkali metal ion, an alkaline earth metal ion,ammonium ion, and combinations of any two or more thereof; and R' is thesame as that disclosed above.

Alternatively, a salt of a mercaptan can also be prepared in-situ bycontacting a halo-substituted aromatic compound with a mercaptan R'SHand either a metal hydroxide MOH or ammonium hydroxide where M and R'are the same as described above.

Examples of suitable salts of mercaptans include, but are not limitedto, sodium isopropanethiolate, potassium isopropanethiolate, ammoniumisopropanethiolate, calcium isopropanethiolate, sodium benzylmercaptide, potassium benzyl mercaptide, ammonium benzyl mercaptide,calcium benzyl mercaptide, sodium methanethiolate, sodiumethanethiolate, sodium cyclohexanethiolate, potassium methanethiolate,potassium ethanethiolate, ammonium methanethiolate, ammoniumethanethiolate, and combinations of any two or more thereof.

These suitable salts of mercaptans are either available commercially orcan be made by well known methods such as reaction of a mercaptan R'SHwith a metal hydroxide MOH, ammonium hydroxide, a base such as, forexample, sodium carbonate, sodium bicarbonate, potassium carbonate,potassium bicarbonate, or combinations of any two or more thereof whereM and R' are the same as described above. Because these methods are wellknown to those skilled in the art, the description of which is omittedherein for the interest of brevity.

According to the present invention, an aqueous medium denotes, unlessotherwise indicated, a reaction medium which does not contain an organicsolvent, for the contact of a halo-substituted aromatic compound and asalt of a mercaptan. However, it can also comprise an organic solventsuch as, for example, toluene. Generally, an aqueous medium can compriseregular tap water, deionized water, distilled water, a solution, asuspension, and combinations of any two or more thereof. Presently it ispreferred that regular tap water be used because it is readily availableand economical. According to the present invention, any surfactant thatfacilitates the mixing of reactants into substantially a single phasecan be used.

Generally, the surfactant comprises one or more compounds which exhibitsurface-active properties. A preferred surfactant for use in thereaction system of the instant invention is selected from the groupconsisting of alkoxylated compounds, quaternary ammonium salts, alkalimetal alkyl sulfates, alkali metal salts of alkanoic acids, alkali metalsalts of alkaryl sulfonic acids, 1-alkyl pyridinium salts, andcombinations of any two or more thereof.

The presently preferred surfactant is an alkoxylated compound. Examplesof suitable alkoxylated compounds include, but are not limited to,alkoxylated alcohols, alkoxylated mercaptans, sulfates of alkoxylatedalcohols, alkoxylated phenols, sulfates of alkoxylated phenols, andcombinations of any two or more thereof.

The alkoxylated alcohol useful in the present invention has a generalformula of R² O[CH₂ CH(R³)O]_(q) H where R² is a C₁ -C₂₀ hydrocarbylradical selected from the group consisting of alkyl radical, alkylarylradical, aryl radical, cycloalkyl radical, alkenyl radical, andcombinations of any two or more thereof; Preferably R² is a C₆ -C₁₈alkyl radical. Most preferably R² is a C₁₀ -C₁₆ alkyl radical; R³ isselected from the group consisting of hydrogen, C₁ -C₁₆ alkyl radicals,C₂ -C₁₆ alkenyl radicals, and combinations of any two or more thereof;and q is a number of from 1 to about 20, preferably from about 2 toabout 12, most preferably from 5 to 10. Generally R³ can contain from 0to about 16 carbon atoms. Preferably R³ is a hydrogen or a C₁ -C₃ alkylradical. Most preferably R³ is hydrogen. An example of suitablealkoxylated alcohol is TERGITOL® 15-S-7 which is an ethoxylated alcohol,is manufactured and marketed by Union Carbide Corporation, and has theformula of R² O(CH₂ CH₂ O)₇ H where R² is a secondary alkyl radicalhaving 11-15 carbon atoms and 7 is the averaged number of the ethyleneoxide units. Another example is an ethoxylated phenol having the samenumber of ethylene oxide units. Other suitable alkoxylated alcohols arealso available from Union Carbide Corporation.

The sulfate of alkoxylated alcohol useful in the present invention has ageneral formula of R² O[CH₂ CH(R³)O]_(q) SO₃ M where R², R³, and q arethe same as those described above and M is an alkali metal or analkaline earth metal or combinations of any two or more thereof. Anexample of suitable sulfate of alkoxylated alcohol is sodium sulfate ofan ethoxylated alcohol having the formula of R² O(CH₂ CH₂)_(q) SO₃ Na inwhich R² and q are the same as those disclosed above.

Useful alkoxylated phenols and sulfates of alkoxylated phenols can havegeneral formulas of (R³)_(p) Ar'O[CH₂ CH(R³)O]_(q) H and (R²)_(p)Ar'O[CH₂ CH(R³)]_(q) SO₃ M, respectively where R², R³, q and M are thesame as those disclosed above, Ar' is a phenyl group and p is an integerranging from 0 to 5. Examples of these alkoxylated phenols areethoxylated phenol Ar'O(CH₂ CH₂ O)_(q) H and sodium sulfate ofethoxylated phenol Ar'O(CH₂ CH₂ O)_(q) SO₃ Na where Ar and q are thesame as disclosed above.

The alkoxylated mercaptan useful in the present invention has a generalformula of R² S[CH₂ CH(R³)O]_(q) H where R², R³, and q are the same asthose described above. An example of an alkoxylated mercaptan is anethoxylated mercaptan having the formula of R² S(CH₂ CH₂ O)₇ H where R²is primarily a tertiary dodecyl group and 7 is the averaged number ofethylene oxide units. This ethoxylated mercaptan is a surfactant,commercially available from Phillips Petroleum Company, Bartlesville,Okla. under the trade name AQUA-CLEEN® II. Another example is anethoxylated thiophenol having the same number of ethylene oxide units.Other suitable alkoxylated mercaptans are also available from PhillipsPetroleum Company.

Quaternary ammonium salt useful in the present invention has the generalformula (R⁴)₄ N⁺ X⁻ where R⁴ is an alkyl radical of from 1 to 20 carbonatoms; and X is selected from the group consisting of Br⁻, Cl⁻, I⁻, F⁻,R⁴ CO₂ ⁻, QSO₃ ⁻, BF₄ ⁻, and HSO₄ ⁻, where Q is an aryl, alkaryl orarylalkyl radical of 6 to 10 carbon atoms. It will be noted that avariety of anions are suitable as the component of the quaternaryammonium salts.

Useful quaternary ammonium salts according to the general formula givenabove include, but are not limited to, methyltrialkyl(C₈ -C₁₀)ammoniumchloride (also known as Adogen® 464), cetyltrimethylammonium bromide,hexadecyltrimethylammonium bromide, tetraheptylammonium bromide,cetyltrimethylammonium stearate, benzyltributylammonium chloride,benzyltriethylammonium bromide, benzyltrimethylammonium bromide,phenyltrimethylammonium bromide, phenyltrimethylammonium iodide,tetrabutylammonium bromide, tetrabutylammonium chloride,tetrabutylammonium hydrogen sulfate, tetrabutylammonium iodide,tetraethylammonium bromide, tetrabutyl ammonium fluoride,tetrabutylammonium tetrafluoroborate, and combinations of any two ormore thereof.

An alkali metal alkyl sulfate of the general formula of R⁴ OSO₃ M can beused in the present invention, wherein R⁴ and M are the same as thosedisclosed above. Examples of suitable compounds according to the generalformula for the alkali metal alkyl sulfates include, but are not limitedto, lithium decylsulfate, potassium dodecylsulfate, sodiumdodecylsulfate, sodium hexadecylsulfate, potassium hexadecylsulfate,rubidium dodecylsulfate, cesium dodecylsulfate, sodium octadecylsulfate,potassium octadecylsulfate, potassium eicosylsulfate, sodiumeicosylsulfate, and combinations of any two or more thereof.

Useful alkali metal salts of alkanoic acids have the general formula ofR⁴ CO₂ M, where R⁴ and M have the same meaning as given above. Examplesof suitable alkali metal salts of alkanoic acids include, but are notlimited to, lithium decanoate, sodium dodecanoate, potassiumdodecanoate, rubidium dodecanoate, cesium dodecanoate, sodiumhexadecanoate, potassium hexadecanoate, sodium octadecanoate, potassiumoctadecanoate, sodium eicosanoate, potassium eicosanoate, andcombinations of any two or more thereof.

Useful alkali metal salts of alkaryl sulfonic acids have the generalformula of (R⁴)_(p) ArSO₃ M where R⁴ and M are the same as thosedisclosed above, Ar is a phenyl group, and p is an integer ranging from0 to 5.

Typical compounds within the group include, but are not limited to,sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate,lithium dodecylbenzenesulfonate, sodium tetradecylbenzenesulfonate,potassium hexadecylbenzenesulfonate, rubidium dodecylbenzenesulfonate,cesium dodecylbenzenesulfonate, sodium octadecylbenzenesulfonate,potassium octadecylbenzenesulfonate, sodium eicosylbenzenesulfonate, andcombinations of any two or more thereof.

Examples of suitable 1-alkyl pyridinium salts include, but are notlimited to, 1-dodecylpyridinium para-toluenesulfonate,1-dodecylpyridinium chloride, 1-hexadecylpyridinium chloride,1-hexadecylpyridinium paratoluenesulfonate, 1-decylpyridinium chloride,1-hexadecylpyridinium bromide, 1-tetradecylpyridinium chloride,1-octadecylpyridinium chloride, 1-eicosylpyridinium chloride,1-octadecylpyridinium benzenesulfonate, and combinations of any two ormore thereof.

The mole ratio of a halo-substituted aromatic compound to a salt of amercaptan can vary widely so long as the ratio can effect the synthesisof an aromatic thioether can be in the range of from about 1:1 to about1:100, preferably from about 1:1 to about 1:15, more preferably about1:1 to about 1:10, and most preferably 1:1 to 1:5, for best results.

The weight ratio of a halo-substituted aromatic compound to a surfactantcan vary widely and can be any ratio that can catalyze reaction of ahalo-substituted aromatic compound and a salt of a mercaptan. Generallythe ratio can be in the range of from about 100,000:1 to about 1:1,preferably about 10,000:1 to about 2:1, more preferably about 5,000:1 toabout 5:1, and most preferably 1,000:1 to 10:1.

Conditions for contacting a halo-substituted aromatic compound with asalt of a mercaptan are any suitable conditions that can result in thesynthesis of an aromatic sulfide and can include an ambient temperaturein the range of from about 0° C. to about 250° C., preferably from about10° C. to about 175° C., and most preferably from 25° C. to 150° C., fora time of from about 1 second to about 20 hours, preferably about 1minute to about 15 hours, and most preferably 10 minutes to 10 hours.The pressure can vary widely from about 0.1 atmosphere to about 30atmospheres, preferably from about 0.1 atmosphere to about 3atmospheres.

Upon completion of the contacting, the product can be used as is or canbe further processed such as washing with water, separations, spargingwith an inert gas, distillation or purification by any methods known toone skilled in the art.

The following examples are provided to further illustrate the practiceof the invention and are not intended to limit the scope of theinvention of the claims.

EXAMPLE I

This example illustrates one way of practicing the process of theinvention.

To a 2 liter, 3-necked flask equipped with a thermowell, magneticstirring bar, pressure equalizing addition funnel, and condenser with N₂inlet on top it was added 250 g of 2,3-dichloronitrobenzene (meltingpoint 61°-62° C.), 350 g of water, and 5 g of Adogen® 464(methyltrialkyl(C₈ -C₁₀)ammonium chloride, obtained from AldrichChemical Co., Inc.). The mixture was heated to 65° C. From the additionfunnel was then added an aqueous solution of the sodium salt ofisopropyl mercaptan (see below for preparation) at a rate to keep thereaction temperature at 65° C. About 20 minutes were required for theaddition and the temperature was easily controlled with some cooling.The mixture was then stirred for 1 hour at 65° C. Stirring was stoppedand the phases were allowed to separate at 65° C. The bottom productphase was separated from the top aqueous NaCl phase. The product phasewas then washed with 300 ml of water. The aqueous phase again was ontop. It was necessary to keep the temperature at 65°-70° C. because theproduct has a melting point of 62°-66° C. The product layer was spargedwith N₂ at 2 SCFH (standard cubic feet per hour) at 70° C. for 3 hoursto remove water. The final product weighed 302 g (100% yield) andsolidified on cooling (melting point 62°-66° C.). The color of theproduct was orange red. GC analysis revealed that the product purity was96%. GC analysis was done with a 20 in. by 1/8 in. OV-101 columnstarting at 50° C. and then 15° C./minute to 215° C. for 10 minutes.

The aqueous solution of the sodium salt of isopropyl mercaptan which wasused in the above procedure was prepared as follows. To a one liter3-necked flask equipped with thermowell, magnetic stirring bar, pressureequalizing addition funnel, and condenser with N₂ inlet on top it wasadded 120 g of 50% NaOH solution and 190 g of water. By the additionfunnel it was added 118 g of isopropyl mercaptan over 15 minutes withstirring. The temperature of the stirred solution rose but was easilycontrolled with cooling. The solution of the sodium salt of isopropylmercaptan which was protected from air by N₂, was used in the aboveexample.

EXAMPLE II

This example illustrates the process of the invention by reverseaddition of 2,3-dichloronitrobenzene to a salt of a mercaptan.

To a 2-liter, 3-necked flask equipped with a thermowell, magneticstirring bar, pressure equalizing addition funnel, and condenser with N₂inlet on top it was added 120 g of 50% NaOH solution, 540 g of water,and 5 g of Adogen® 464. By the addition funnel was added 118 g ofisopropyl mercaptan in portions over 15 minutes with stirring. Thetemperature rose but was easily controlled by cooling. The solution washeated to 65° C. Then 250 g of solid 2,3-dichloronitrobenzene (thiscould also be added molten, mp 61°-62° C.) was added in portions at arate, so the reaction mixture stayed at 65° C. About 20 minutes wererequired for the addition, and the temperature was easily controlled bysome cooling. The reaction mixture was stirred for one hour at 65° C.The remainder of the process was the same as described in Example Iabove. GC analysis showed that the yield of orange red solid product was100% and the purity of the product was 96%.

EXAMPLE III

This example illustrates the use of a different surfactant forpracticing the process of the invention.

The run was carried out the same as that described in Example I exceptthat 25 g of 2,3-dichloronitrobenzene, 35 g of water, and 2.0 g ofTERGITOL® 15-S-7 (obtained from Union Carbide Corporation) were used,the sodium salt of isopropyl mercaptan was made from 25 g of water, 6.0g of NaOH pellets, and 11.8 g of isopropyl mercaptan, and the reactiontime was 8 hours. GC analysis showed that the product was obtained in100% yield with a purity of 95%.

EXAMPLE IV

This example is a comparative example showing that without using asurfactant the reaction rate was slow, the conversion was low, and theproduct was contaminated with undesired by-products.

The run was carried out the same as that described in Example II withthe exception that the surfactant Adogen® 464 was not present in thereaction medium. After 1 hour, the reaction was only 10% complete. Thereaction temperature was then increased to 80° C. After 3 hours at 80°C., the reaction was only 50% complete. Even after 6 hours at 80° C.,the reaction was only about 65% complete and the product was found to becontaminated with about 10% heavies (i.e., molecular weights higher thanthe desired product).

The results shown in the above examples clearly demonstrate that thepresent invention is well adapted to carry out the objects and attainthe ends and advantages mentioned was well as those inherent therein.While modifications may be made by those skilled in the art, suchmodifications are encompassed within the spirit of the present inventionas defined by the disclosure and the claims.

That which is claimed:
 1. A process for producing an aromatic sulfidecomprising contacting, in the presence of a surfactant, ahalo-substituted aromatic compound in an aqueous medium with a salt ofmercaptan wherein:said aromatic sulfide compound has the formula of

    (R.sub.4-n)(X.sub.n)(W)Ar--S--R';

each R is independently selected from the group consisting of hydrogen,hydrocarbyl radicals each having 1 to about 30 carbon atoms, andcombinations of any two or more thereof wherein said hydrocarbyl radicalis selected from the group consisting of alkyl radicals, akenylradicals, aryl radicals, alkaryl radicals, aralkyl radicals, cycloalkylradicals, cycloalkenyl radicals, and combinations of any two or morethereof; each X is a halogen; n is an integer from 0 to 3; W is asubstituent selected from the group consisting of --NO₂, --SO₃ H, --CHO,--COOH, ×NO, --N⁺ ₂, --CN, --COR, --COO', SO₃ ⁻, --SO₂ CH₃, --CF₃, and--N⁺ (CH₃)₃ ; Ar is selected from the group consisting of naphthylgroup, phenyl group, and biphenyl group; R' is selected from the groupconsisting of alkyl radicals, akenyl radicals, cycloalkyl radicals, andcycloalkenyl radicals; said halo-substituted aromatic compound has theformula of

    (R.sub.4-n)(X.sub.n+1)WAr;

said salt of mercaptan has the formula of MSR' wherein M is selectedfrom the group consisting of alkali metal ions, alkaline earth metalions, ammonium ions, and combinations of any two or more thereof; andsaid surfactant is selected from the group consisting of alkoxylatedcompounds, quaternary ammonium salts, alkali metal alkyl sulfates,alkali metal salts of alkanoic acids, alkali metal salts of alkarylsulfonic acids, 1-alkyl pyridinium salts, and combinations of any two ormore thereof wherein said alkoxylated compound is selected from thegroup consisting of alkoxylated mercaptans, alkoxylated phenols,sulfates of alkoxylated phenols, and combinations of any two or morethereof.
 2. A process according to claim 1 wherein said hydrocarbylradical has 1 to 15 carbon atoms, X is chlorine, and n is
 1. 3. Aprocess according to claim 1 wherein said aromatic sulfide is selectedfrom the group consisting of 2-chloro-6-nitrophenyl isopropyl sulfide,3-chloro-6-nitrophenyl isopropyl sulfide, 4-chloro-6-nitrophenylisopropyl sulfide, 2-chloro-6-nitrophenyl methyl sulfide,3-chloro-6-nitrophenyl methyl sulfide, 4-chloro-6-nitrophenyl methylsulfide, 3-chloro-6-nitrophenyl cyclohexyl sulfide, 4-nitrophenyl methylsulfide, 4-nitrophenyl isopropyl sulfide, 3-nitrophenyl methyl sulfide,3-nitrophenyl isopropyl sulfide, 4-methylthiomethylbenzoate, andcombinations of any two or more thereof.
 4. A process according to claim1 wherein said aromatic sulfide is 2-chloro-6-nitrophenyl isopropylsulfide.
 5. A process according to claim 1 wherein said halo-substitutedaromatic compound is selected from the group consisting of2,3-dichloronitrobenzene, 3,4-dichloronitrobenzene,2,4-dichloronitrobenzene, 2,3-difluoronitrobenzene,3,4-difluoronitrobenzene, 2,4-difluoronitrobenzene,2,3-dibromonitrobenzene, 3,4-dibromonitrobenzene,2,4-dibromonitrobenzene, 2,4-dichloro-5-nitrotoluene,3,4-dichloro-5-nitrobenzene, 4-chlorobenzaldehyde, 4-bromobenzaldehyde,4-iodobenzaldehyde, 3-chlorobenzaldehyde, 3-bromobenzaldehyde,4-chlorobenzoic acid, 4-bromobenzoic acid, 3-iodobenzoic acid,4-chloromethylbenzoate, 4-bromomethylbenzoate, and combinations of anytwo or more thereof.
 6. A process according to claim 1 wherein saidhalo-substituted aromatic compound is 2,3-dichloronitrobenzene.
 7. Aprocess according to claim 1 wherein said salt of mercaptan is selectedfrom the group consisting of sodium isopropanethiolate, potassiumisopropanethiolate, ammonium isopropanethiolate, calciumisopropanethiolate, sodium methanethiolate, sodium ethanethiolate,sodium cyclohexanethiolate, potassium methanethiolate, potassiumethanethiolate, ammonium methanethiolate, ammonium ethanethiolate, andcombinations of any two or more thereof.
 8. A process according to claim1 wherein said salt of mercaptan is sodium isopropanethiolate.
 9. Aprocess according to claim 1 wherein said aqueous medium is water.
 10. Aprocess according to claim 1 wherein said surfactant is a quaternaryammonium salt.
 11. A process according to claim 1 wherein saidsurfactant is methyltrialkyl(C₈ -C₁₀)ammonium chloride which is alsoknown as Adogen®
 464. 12. A process according to claim 1 wherein:saidaromatic sulfide is selected from the group consisting of2-chloro-6-nitrophenyl isopropyl sulfide, 3-chloro-6-nitrophenyl benzylsulfide, 3-chloro-6-nitrophenyl isopropyl sulfide,4-chloro-6-nitrophenyl isopropyl sulfide, 2-chloro-6-nitrophenyl methylsulfide, 3-chloro-6-nitrophenyl methyl sulfide, 4-chloro-6-nitrophenylmethyl sulfide, 3-chloro-6-nitrophenyl cyclohexyl sulfide, 4-nitrophenylmethyl sulfide, 4-nitrophenyl isopropyl sulfide, 3-nitrophenyl isopropylsulfide, and combinations of any two or more thereof, or saidhalo-substituted aromatic compound is selected from the group consistingof 2,3-dichloronitrobenzene, 3,4-dichloronitrobenzene,2,4-dichloronitrobenzene, 2,3-difluoronitrobenzene,3,4-difluoronitrobenzene, 2,4-difluoronitrobenzene,2,3-dibromonitrobenzene, 3,4-dibromonitrobenzene,2,4-dibromonitrobenzene, 2,4-dichloro-5-nitrotoluene,3,4-dichloro-5-nitrobenzene, 4-chlorobenzaldehyde, 4-bromobenzaldehyde,4-iodobenzaldehyde, 3-chlorobenzaldehyde, 3-bromobenzaldehyde,4-chlorobenzoic acid, 4-bromobenzoic acid, 3-iodobenzoic acid,4-chloromethylbenzoate, 4-bromomethylbenzoate, and combinations of anytwo or more thereof; said salt of mercaptan is selected from the groupconsisting of sodium isopropanethiolate, potassium isopropanethiolate,ammonium isopropanethiolate, calcium isopropanethiolate, sodiummethanethiolate, sodium ethanethiolate, sodium cyclohexanethiolate,potassium methanethiolate, potassium ethanethiolate, ammoniummethanethiolate, ammonium ethanethiolate, and combinations of any two ormore thereof; and said surfactant is selected from the group consistingof quaternary ammonium salts, alkoxylated compounds, and combinations ofany two or more thereof.
 13. A process according to claim 1 wherein saidaromatic sulfide is 2-chloro-6-nitrophenyl isopropyl sulfide; saidhalo-substituted aromatic compound is 2,3-dichlorobenzene; said salt ofmercaptan is sodium isopropanethiolate; said surfactant ismethyltrialkyl(C₈ -C₁₀)ammonium chloride which is also known as Adogen®464; and said aqueous medium is water.
 14. A process for producing2-chloro-6-nitrophenyl isopropyl sulfide comprises contacting, in thepresence of methyltrialkyl(C₈ -C₁₀)ammonium chloride,2,3-dichloronitrobenzene with sodium isopropanethiolate in an aqueousmedium.
 15. A process according to claim 1 wherein each of saidhydrocarbyl radials has 1 to about 20 carbon atoms.
 16. A processaccording to claim 1 wherein each of said hydrocarbyl radials has 1 to15 carbon atoms.
 17. A process according to claim 1 wherein W is --NO₂.18. A process according to claim 1 wherein said Ar is a phenylene group.19. A process according to claim 14 wherein said aqueous medium iswater.
 20. A process according to claim 1 wherein said process iscarried out at 65° to 70° C.
 21. A process according to claim 1 whereinR is selected from the group consisting of hydrogen, hydrocarbylradicals each having 1 to 15 carbon atoms, and combinations of any twoor more thereof; X is chlorine; W is --NO₂ ; Ar is a phenyl group; R' isan alkyl radical having 1 to 15 carbon atoms; M is an alkali metal; andsaid surfactant is a quaternary ammonium salt.
 22. A process accordingto claim 21 wherein said process is carried out at 65° to 70° C.
 23. Aprocess for producing 2-chloro-6-nitrophenyl isopropyl sulfidecomprising contacting,. in the presence of methyltrialkyl(C₈-C₁₀)ammonium chloride, 2,3-dichloronitrobenzene with sodiumisopropanethiolate in an aqueous medium and at 65° to 70° C.